//题目：画图，综合例子。
//1.程序分析：
//2.程序源代码：
#if FALSE
#include "graphics.h"
#define LEFT 0
#define TOP 0
#define RIGHT 639
#define BOTTOM 479
#define LINES 400
#define MAXCOLOR 15
main() {
	int driver, mode, error;
	int x1, y1;
	int x2, y2;
	int dx1, dy1, dx2, dy2, i = 1;
	int count = 0;
	int color = 0;
	driver = VGA;
	mode = VGAHI;
	initgraph(&driver, &mode, "");
	x1 = x2 = y1 = y2 = 10;
	dx1 = dy1 = 2;
	dx2 = dy2 = 3;
	while (!kbhit()) {
		line(x1, y1, x2, y2);
		x1 += dx1;
		y1 += dy1;
		x2 += dx2;
		y2 + dy2;
		if (x1 <= LEFT || x1 >= RIGHT)
		dx1 = -dx1;
		if (y1 <= TOP || y1 >= BOTTOM)
		dy1 = -dy1;
		if (x2 <= LEFT || x2 >= RIGHT)
		dx2 = -dx2;
		if (y2 <= TOP || y2 >= BOTTOM)
		dy2 = -dy2;
		if (++count > LINES) {
			setcolor(color);
			color = (color >= MAXCOLOR) ? 0 : ++color;
		}
	}
	closegraph();
}
#endif
